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#### Description Kamailio TLS mod_init is creating one SSL_CTX, per process, some of the fonctions are taking between 1-3 seconds to execute, this is slowing down the startup sequence greatly. ``` SSL_CTX_load_verify_locations SSL_CTX_set_client_CA_list // list sent to the client SSL_load_client_CA_file SSL_CTX_get_client_CA_list ```

In fact it is safe to share the SSL_CTX since it is only used to store settings that will be used to internalize new structure, see the documentation reference : ``` tls: faster startup using shared SSL_CTX

https://www.openssl.org/docs/man1.1.1/man7/ssl.html SSL_CTX (SSL Context) This is the global context structure which is created by a server or client once per program life-time and which holds mainly default values for the SSL structures which are later created for the connections. ```

I load tested this with 1000 TLS connections. We could push the refactoring further, this simple modification as a huge impact since the functions are now called only once per SSL / SNI, not per process ...

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/1585

-- Commit Summary --

* tls: faster startup using shared SSL_CTX

-- File Changes --

M src/modules/tls/tls_domain.c (29)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/1585.patch https://github.com/kamailio/kamailio/pull/1585.diff